Calculators

Methanation / Sabatier Reactor Sizing

Adiabatic fixed-bed sizing for CO&sub2; methanation (Sabatier): CO&sub2; + 4 H&sub2; → CH&sub4; + 2 H&sub2;O. Computes catalyst volume from GHSV, vessel L & D from L/D aspect, adiabatic temperature rise, superficial velocity, and Ergun pressure drop.

Method: Catalyst volume V_cat = Q_NTP / GHSV with Q_NTP = n·22.414 Nm³/kmol. Vessel diameter from L/D: D = (4·V_cat / (π·L/D))^(1/3); L = D·(L/D). Adiabatic temperature rise ΔT_ad = X·n_CO2·(−ΔH_rxn) / (n_tot·Cp_mean). Gas density from ideal-gas. Pressure drop via Ergun (1952): ΔP/L = 150·μ·(1−ε)²/(D_p²·ε³)·u + 1.75·ρ·(1−ε)/(D_p·ε³)·u². Single adiabatic bed shown for screening; industrial SNG plants use 2–4 stage intercooled reactors or cooled tubular (TREMP, MAN ETOGAS) to cap T_max < 650 °C and protect the Ni catalyst. Equilibrium conversion > 99% at T < 300 °C and P > 10 bar; kinetics-limited above 400 °C. Ergun valid for 1 < Re < 1000. References: Rönsch et al., "Review on methanation," Fuel 166 (2016); Gao et al., RSC Adv. 2 (2012); Topsoe TREMP bulletin (2010); Ergun, Chem. Eng. Prog. 48 (1952); Sabatier & Senderens (1902).

© 2026 Inflection Point Engineering, LLC. All rights reserved. The content of this page — including calculation methods, reference data, written analysis, interactive tools, and source code — is the intellectual property of Inflection Point Engineering, LLC and is protected under applicable copyright, trademark, and trade secret laws. Unauthorized reproduction, redistribution, modification, or derivative use in whole or in part is prohibited without prior written consent.

Disclaimer. This material is provided for informational and educational purposes only and does not constitute professional engineering advice. Calculations, reference data, and methodologies are based on published standards and accepted engineering practice but are not a substitute for engineering judgment, site-specific analysis, or review by a licensed Professional Engineer. Inflection Point Engineering, LLC makes no warranties, express or implied, regarding the accuracy, completeness, or fitness for a particular purpose of any content presented here, and shall not be liable for any direct, indirect, incidental, or consequential damages arising from its use. Users assume all risk associated with applying this content to real-world design, operations, or decisions.

Methanation / Sabatier Reactor Sizing

Results